Factors Affecting Rate of Reaction

Q.

Consider the chemical reaction,
$N_2\left(g\right)+3H_2\left(g\right)\to 2N{H}_3\left(g\right)$
The rate of this reaction can be expressed in terms of time derivatives of concentration of $N_2\left(g\right),H_2\left(g\right)orN{H}_3\left(g\right)$. Identify the correct relationship amongst the rate expressions.

1. $Rate=\frac{d\left[N_2\right]}{dt}=\frac{1}{3}\frac{d\left[H_2\right]}{dt}=\frac{1}{2}\frac{d\left[N{H}_3\right]}{dt}$

2. $Rate=-\frac{d\left[N_2\right]}{dt}=-\frac{d\left[H_2\right]}{dt}=\frac{d\left[N{H}_3\right]}{dt}$

3. $Rate=-\frac{d\left[N_2\right]}{dt}=-\frac{1}{3}\frac{d\left[H_2\right]}{dt}=\frac{1}{2}\frac{d\left[N{H}_3\right]}{dt}$

4. $Rate=-\frac{d\left[N_2\right]}{dt}=-3\frac{d\left[H_2\right]}{dt}=2\frac{d\left[N{H}_3\right]}{dt}$