Consider the following two statements:
A. Linear momentum of a system of partcles is zero.
B. Kinetic energ of a system of particles is zero.
A. `1` implies `2` and `2` implies `1`
B. `1` does not imply `2` and `2` does not imply `1`
C. `1` implies `2` but does not imply `1`
D. `1` does not imply `2` but `2` implies `1`
