Given:

Multiplication of $787$ by $67$

To find:

$787\times 67$

Calculation:

We can write $787\times 67$ as,

$787\times 67=787\times (60+7)$

By using Distributive law, we get, 

$787\times 67=(787\times 60)+(787\times 7)$ -----$\left(1\right)$

Therefore, dividing the question into two steps,

$\Rightarrow 787\times 60=47220$ -----$\left(2\right)$

$\Rightarrow 787\times 7=5509$ -----$\left(3\right)$

Substituting values of $\left(2\right)$ & $\left(3\right)$ in $\left(1\right)$, we get,

$787\times 67=47220+5509$

               $=52729$

Therefore, the product of $787$ & $67$ is $52729$.

Hence, the correct option is 'A'.