Sentence Correction

Source: Master The GMAT 2010

The volatility of a balanced portfolio of stocks and bonds, less than 80 percent of the overall stock market.

A: The volatility of a balanced portfolio of stocks and bonds, less than 80 percent of the overall stock market.
B: A balanced portfolio of stocks and bonds is less than 80 percent as volatile as the overall stock market.
C: A balanced portfolio of stocks and bonds is less than 80 percent as volatile as that of the overall stock market.
D: Volatility is less than 80 percent for a balanced portfolio of stocks and bonds compared to the overall stock market.
E: The volatility of a balanced portfolio of stocks and bonds is less than 80 percent of the overall stock market.

How to select between B and C? What comparison is going on here?

OA: B

Comparison :The volatility of a balanced portfolio of stocks and bonds Vs The volatility of the overall stock market.


I am going with C!

Refer OG 10, 51 SC

While Jackie Robinson was a Brooklyn Dodger, his courage in the face of physical threats and verbal attacks was not unlike that of Rosa Parks, who refused to move to the back of a bus in Montgomery, Alabama.
(A) not unlike that of Rosa Parks, who refused
(B) not unlike Rosa Parks, who refused
(C) like (Rosa Parks and her refusal
(D) like that of Rosa Parks for refusing
(E) as that of Rosa Parks, who refused

what's thge OA?

Clearly the answer is B. Except B all the other choices have comparison problems.

A) Awkward construction (no verb) + wrong comparison.
C) 'that of' in C is redundant
D) wrong comparison. "Volatility for a balanced portfolio" is being compared to overall stock market instead of "volatility of overall stock market".
E) Little different sentence structure but same error as that in D. "Volatility of a balanced portfolio" is being compared to overall stock market instead of "volatility of overall stock market".

Hope that helps.

gmatmachoman wrote: Comparison :The volatility of a balanced portfolio of stocks and bonds Vs The volatility of the overall stock market.


I am going with C!

Your explanation is correct but you selected wrong answer.
Actually, here main thing is that one should understand the use and meaning of AS ... AS construction.

I understood it now. THAT OF is not requited.

akhp77 wrote:Source: Master The GMAT 2010

The volatility of a balanced portfolio of stocks and bonds, less than 80 percent of the overall stock market.

A: The volatility of a balanced portfolio of stocks and bonds, less than 80 percent of the overall stock market.
B: A balanced portfolio of stocks and bonds is less than 80 percent as volatile as the overall stock market.
C: A balanced portfolio of stocks and bonds is less than 80 percent as volatile as that of the overall stock market.
D: Volatility is less than 80 percent for a balanced portfolio of stocks and bonds compared to the overall stock market.
E: The volatility of a balanced portfolio of stocks and bonds is less than 80 percent of the overall stock market.

How to select between B and C? What comparison is going on here?

OA: B

A balanced portfolio is 80% as volatile as the overall stock market IS

So B is perfect here.

Ah! Finally an easy one! It is the as X as Y construction in play here and B is clearly the answer. IN C that of is referring to nothing.

gmatmachoman wrote:Comparison :The volatility of a balanced portfolio of stocks and bonds Vs The volatility of the overall stock market.


I am going with C!

Refer OG 10, 51 SC

While Jackie Robinson was a Brooklyn Dodger, his courage in the face of physical threats and verbal attacks was not unlike that of Rosa Parks, who refused to move to the back of a bus in Montgomery, Alabama.
(A) not unlike that of Rosa Parks, who refused
(B) not unlike Rosa Parks, who refused
(C) like (Rosa Parks and her refusal
(D) like that of Rosa Parks for refusing
(E) as that of Rosa Parks, who refused

That refers to courage in the OG question whereas that has no referent in question posted by the OP. as X is as volatile as Y IDIOM

akhp77 wrote:Source: Master The GMAT 2010

The volatility of a balanced portfolio of stocks and bonds, less than 80 percent of the overall stock market.

A: The volatility of a balanced portfolio of stocks and bonds, less than 80 percent of the overall stock market.
B: A balanced portfolio of stocks and bonds is less than 80 percent as volatile as the overall stock market.
C: A balanced portfolio of stocks and bonds is less than 80 percent as volatile as that of the overall stock market.
D: Volatility is less than 80 percent for a balanced portfolio of stocks and bonds compared to the overall stock market.
E: The volatility of a balanced portfolio of stocks and bonds is less than 80 percent of the overall stock market.

How to select between B and C? What comparison is going on here?

OA: B

Plz put your DOUBT too under spoiler....

thanks!

gmatmachoman wrote:Comparison :The volatility of a balanced portfolio of stocks and bonds Vs The volatility of the overall stock market.


I am going with C!

Refer OG 10, 51 SC

While Jackie Robinson was a Brooklyn Dodger, his courage in the face of physical threats and verbal attacks was not unlike that of Rosa Parks, who refused to move to the back of a bus in Montgomery, Alabama.
(A) not unlike that of Rosa Parks, who refused
(B) not unlike Rosa Parks, who refused
(C) like (Rosa Parks and her refusal
(D) like that of Rosa Parks for refusing
(E) as that of Rosa Parks, who refused

IMO D

Right Machoman... ?