If 1 is added to each odd digit and 1 is subtracted from each even digit in the number 8146752, what will be the difference between the last and first digits from the left in the new number thus formed?

Given: 8146752.

Add 1 to each odd digit and subtract 1 from each even digit.

8 is even → 8 − 1 = 7

1 is odd → 1 + 1 = 2

4 is even → 4 − 1 = 3

6 is even → 6 − 1 = 5

7 is odd → 7 + 1 = 8

5 is odd → 5 + 1 = 6

2 is even → 2 − 1 = 1

The new number formed: 7235861

The first digit = 7

The last digit = 1

Difference: 7 − 1 = 6

So, 6 will be the difference between the last and first digits from the left in the new number thus formed.

Thus, correct option is (c).