. . . . . . . . sun shines very brightly in summer.

A. An

B. A

C. The

D. That

Answer: Option C

Solution(By Examveda Team)

"The" is a definite article which is used before a noun that is fixed, special or discussed earlier. "A/An" is used before an indefinite singular noun. "Sun" is a fixed noun. Hence "the" will be used.
The sun shines very brightly in summer.