Many of our coaches are the same well-known skiers that you have seen (           ) in magazines and televised competitions

(a)featured

(b)features

답이 (a)라고 합니다. skiers were featured....라고 설명하던데요, 그리고 이게 답이라면 were가 왜 생략이 되어야 하는지요?

또, you have seen이 아니라had seen이 되어야 되지 않나요?

전, skiers가 선행사로 보고 that 절을 목적격관계사절로 봤거든요,,,답도(b)features라고 했구요