Which of the following pairs is not correctly matched?

PYQ UPPSC LT Grade (Assistant Teacher) 2025

1. A.

   div r⃗ = 3

2. B.

   If r⃗ = xî + yĵ + zk̂ and r = |r⃗|, then curl r⃗ is: 0⃗

3. C.

   div r̂ = 2r

4. D.

   div (curl r⃗) = 0

Attempted by 6 students.