[单选题]
A box is sliding downw/p,ni e th;0tb zla (89*t g;xicnvo, an incli hxeh f)dx80,mne at a constant speed of $2\,ms^{−1}$. The angle of the incline is $\theta$.
The magnitude of the total of the opposing forces is $16\,N$. What is the force of gravity acting on the box?
A. $\frac{8}{sin \theta}$
B. $\frac{16}{sin \theta}$
C. $\frac{8}{cos \theta}$
D. $\frac{16}{cos \theta}$
