Choose symbol sequence — Replace * to balance: 7 * 7 * 2 * 1 = 12

Introduction / Context:
We must select a fixed sequence of three operators to make the equation true. Standard precedence applies.

Given Data / Assumptions:

• Template: 7 {s1} 7 {s2} 2 {s3} 1 = 12.

Concept / Approach:
Test reasonable combinations; subtraction and multiplication often help reach small targets like 12.

Step-by-Step Solution:

Verification / Alternative check:
Explicitly compute each alternative; only Option B balances.

Why Other Options Are Wrong:

• They produce values like 47, 12 by chance only if precedence is ignored, or other mismatches.

Common Pitfalls:

• Ignoring that × takes precedence over +/−.

Final Answer:
+ - x