In the given figure, how many people study only $ 2 $ subjects?

A. $ 11 $
B. $ 23 $
C. $ 12 $
D. $ 40 $

Hint: Here we are given a Venn diagram which represents the mathematical or logical sets as circles and also common elements of the sets which represent the intersection of the circles. Follow the condition where people only study two subjects.

Complete step-by-step answer:
To find the people who study exactly subjects are-
First of all find the intersection for two subjects-
The people who studied Mathematics and chemistry - The total count of the people is the intersection between the mathematics and the chemistry subject.
Therefore, the people who studied Mathematics and chemistry $ = 6 $ ... (a)
The People who studied Chemistry and Physics - The total count of the people is the intersection between the chemistry and the Physics subject.
Therefore, the people who studied chemistry and the Physics $ = 12 $ .... (b)
The people who studied Physics and Mathematics – The total count of the people is the intersection between Physics and Mathematics.
Therefore, the people who studied Physics and Mathematics $ = 5 $ .... (c)
By using the values of the equation (a), (b) and (c)
Altogether, the total people who studied only two subjects is
 $ = 6 + 12 + 5 $
Simplify the above expression –
 $ = 23 $
So, the correct answer is “Option B”.

Note: Be careful while observing the intersection of two sets and three sets and the respective values. Also, read the question twice for the required condition to be followed and understand first then start solving it.