A：It's brown.
B：It's a bag.
温度/℃
0
20
40
60
80
溶解度/g
13.3
31.6
63.9
110
169
则下列说法正确的是（ ）
巴西的首都巴西利亚地处热带,却四季如春,其主要原因是 ( )
He devoted all his efforts _______ children.
