The digit in the unit's place of the product 61 × 62 × 63........ × 69 is:

Correct option is A

Given:

Product of numbers from 61 to 69, i.e., 61 × 62 × 63 × ⋯ × 69

Concept Used:
Basic unit digit rules and
If product includes 5 × even number

unit digit = 0

Solution:
Among the numbers from 61 to 69:

65 ends with 5

62, 64, 66, 68 are even numbers

So, 65 × 64 (or any other even number) will have unit digit = 0.
Hence, entire product ends with 0.