I was standing in the sun on the hot steel deck of a fishing ship capable of processing a fifty-ton catch on a good day.
句意：我头顶烈日站在一艘渔船的滚烫的钢甲板上。这艘渔船在丰收季节一天所处理加工的鱼可达 15吨。in the sun指在阳光下。C选项与划线处意义最为接近，故选C。