busy with/ doing sth

[san2612]

1. She was busy_________ a variety of articles to the customers
A with introducing
B introducing
C for introducing
D in introducing

I chose the correct answer (B). But I don't know the difference between
Busy with doing sth
and busy doing sth

 

[emsr2d2]

1. She was busy_________ a variety of articles to the customers
A with introducing
B introducing
C for introducing
D in introducing

I chose the correct answer (B). But I don't know the difference between
Busy with doing sth
and busy doing sth

We're usually "busy + verb" and "busy with + noun".

I'm busy watching TV.
I'm busy with a friend and we're watching TV.

Is John available?
I'm sorry, he's busy with a customer.

Is John available?
I'm sorry, he's busy serving a customer.