1/a × 1/b = 1, then the value of a-b-c is:

by

A) 0
B) 1
C) cannot determined
D) -1

🧠 Explanation (Math):

Given: (1/a) × (1/b) = 1; ask value of a − b − c
Step 1: From (1/a)(1/b) = 1 ⇒ ab = 1 (relation between a and b)
Step 2: Expression involves c, which is unspecified
Step 3: Insufficient information to determine a − b − c
Final Answer: cannot determined