Question

suckback is a term used to describe
excessive reinforcement
a root that is concave
a hole in the root pass

Explanation:

In welding terminology, suckback refers to the condition where the root of a weld is concave (curved inward) due to the weld metal being drawn back, typically in processes like TIG welding. "Excessive reinforcement" is incorrect as suckback isn't about excess build - up. "A hole in the root pass" describes a different defect (like a burn - through or hole - type defect, not suckback). So the correct description of suckback is a root that is concave.

Answer:

B. A root that is concave (assuming the options are labeled as A: excessive reinforcement, B: A root that is concave, C: a hole in the root pass)