What is the product of $900\times 10$?

The correct option is (A),

We can do the multiplication of $900\times 10$ using the steps given below. 

Step 1: Multiply 0 by each digit of 900

Step 2: Place a zero on ones place below the product obtained above.

Step 3: Multiply 1 by each digit of 900

Step 4: Add the two products to obtain the final answer.

Therefore, the product of $900\times 10$ is $9000$