Robert had a comfortable childhood, ______ up in a pleasant house with a view of the sea.
A:grew
B:growing
C:grown
D:to grow
母狼失去幼仔后,能将人的婴孩哺育成狼孩,下列对这一行为解释正确的是:( )
①这是先天性行为②这是学习行为③这是由遗传因素决定的④这是由环境因素决定的