397 × 397 + 104 × 104 + 2 × 397 × 104 = ?

Answer: Option B

Given expression,
= (397)² + (104)² + 2 × 397 × 104
= (397 + 104)²
= (501)²
= (500 + 1)²
= (500)² + 1² + 2 × 500 × 1
= 250000 + 1 + 1000
= 251001