Answer:
The correct answer is option 3.
Step-by-step explanation:

To calculate the concentration of acid, we use the equation given by neutralization reaction:

where,
are the n-factor, molarity and volume of acid which is

are the n-factor, molarity and volume of base which is
.
We are given:

Putting values in above equation, we get:


1 mL = 0.001 L

Hence, the correct answer is option 3.