A student is to answer 10 out of 13 questions in an examination such that he must choose at least 4 from the first five questions. The number of choices available to him is

Given, at least 4 questions are to be solved from the first 5 questions. Hence, there are two conditions where he chooses 4 questions from 

the first 5 (or) all 5 questions from the first 5.

(1) If he chooses to write 4 questions from the first 5 and 6 questions from remaining 8,

Then number of ways = $$5_{C_{4}}$$ x $$8_{C_{6}}$$ = 5 x 28 = 140.

(2) If he chooses to write 5 questions from the first 5 and 5 questions from the remaining 8,

Then number of ways = $$5_{C_{5}}$$ x $$8_{C_{5}}$$ = 1 x 56 = 56.

$$\therefore$$ Total number of ways = 140 + 56 =196.

Hence, option C is the correct answer.