In the opening of an argument, it is effective to acknowledge the counterclaim and

1. explain the strong points of the counterclaim
2. point out a problem with the counterclaim
3. provide evidence that supports the counterclaim
4. use quotations to disprove the counterclaim

The answer is B. Point out a problem with the counter claim. Hope this helps

2. point out a problem with the counterclaim

Explanation:

It is effective to make the counterclaim weaker. For example: " Teenagers know how to use technology perferctly well because they are digital natives." This can be the couterclain of this claim: " Digital literacy does not depend on age but on culture."

Therefore, the weak point of the counterclaim could be developed in this way:" The fact that most  teenagers have been in contact with technological devices since they were born does not make them skillful users of technology. They know how to use it superficially but if they are to become good users of it, they have to be taught how to do so."

a is the indefinite article

i believe it is the first option, having taken lessons