The correct answer is "16 + 24".

Solution:
To find the correct answer, we find the sum of each expression by rounding (up or down) the addends.

At Option A:
Round the addends to the nearest tens and then add.

42  +  38  =  ?
↓          ↓
40  +  40  =  80

This expression has a sum nearly equal to 80.

At Option B:

36  +  67  =  ?
↓           ↓
40  +  70  =  110

This expression has a sum nearly equal to 110.

At option C:

16  +  24  =  ?
↓          ↓
20  +  20  =  40

This expression has a sum nearly equal to 40.

At the last option D:

28  +  67  =  ?
↓          ↓
30  +  70  =  100

This expression has a sum nearly equal to 100.

So, the desired answer is "16 + 24".