A straight-A student from The Bronx was shot dead near a relative’s home yesterday after a gunman confronted him to settle a score from an earlier dispute, cops said.

Londell Byrd, 18, of Riverdale, was hit at around 4 p.m. in front of 1411 Noble St. in Soundview, near his grandmother’s house.

His devastated mom said Byrd, her only child, was filling out college applications. “He was a really sweet kid,” said Joann Soto. “I can’t believe it.”

A police source said suspect Jimmy Delgado, 18, remained at large early today.