MAT Exam 2020 Paper

Concept:The letter series grows by forming blocks in which repeated letters increase step by step: $\mathrm{abc},\ \mathrm{aabc},\ \mathrm{aabbc},\ \mathrm{aabbcc}$.Explanation:Fill the blanks using option C: $a,\ b,\ a,\ c$.The completed series is:$\mathrm{abc}\ \mathrm{aabc}\ \mathrm{aabbc}\ \mathrm{aabbcc}\ \mathrm{a}$.Now compare the blank positions with the blocks:$a\_bc$ must become $\mathrm{aabc}$, so the first missing letter is $a$.$aab\_c$ must become $\mathrm{aabbc}$, so the second missing letter is $b$.$a\_bbc\_$ must become $\mathrm{aabbcc}$, so the third and fourth missing letters are $a$ and $c$.Thus the required missing letters are $a,\ b,\ a,\ c$, which matches option C.Answer:Option C: $\mathrm{abac}$