The order of the family of curves $y=(c_1+c_2)e^x+c_3{e}^{x+c_4}$ is

Here, the number of arbitrary parameters is 4 but the order of the corresponding differential equation will not be 4 as it can be rewritten as, $y=(c_1+c_2+c_3{e}^{c_4})e^x,$ which is of the form $y=A{e}^x.$ Hence, the corresponding differential equation will be of order 1.