Spot the error in the following sentence.
A. Having received your letter
B. today, we are writing
C. to thank you for these
D. No error.

C

The correct answer is Option (3) → C ("to thank you for these")

The word "these" is incorrect because "letter" is singular, and "these" is used for plural nouns. The correct word should be "it."

Having received your letter today, we are writing to thank you for it.