The Equation Below Is the Solution to a Physics Problem

The equation below is the solution to a physics problem: $$\frac { 1 } { 2 } ( 2.30 \mathrm {~kg} ) \left( 3.90 \frac { \mathrm { m } } { \mathrm { s } } \right) ^ { 2 } = \frac { 1 } { 2 } ( 2.30 \mathrm {~kg} ) \left( 2.33 \frac { \mathrm { m } } { \mathrm { s } } \right) ^ { 2 } + ( 2.30 \mathrm {~kg} ) \left( 9.80 \frac { \mathrm { m } } { \mathrm { s } ^ { 2 } } \right) ( 1.00 \mathrm {~m} ) \cos \left( 60 ^ { \circ } \right)$$ . The most likely physical situation it describes is

A) a 2.30 kg cart rolling up a 30 $\degree$ incline.
B) a 2.30 kg cart rolling down a 30 $\degree$ incline.
C) a 2.30 kg cart rolling up a 60 $\degree$ incline.
D) a 2.30 kg cart rolling down a 60 $\degree$ incline.
E) a 2.30 kg cart rolling down a 90 $\degree$ incline.