Question

david jumped back from the cupboard as an avalanche of cans tumbled off the shelves. the cans struck the counter, and then bounced onto the hard tiles of the kitchen floor.

remove the comma between counter and and.
no change is necessary.
add a comma between cupboard and as.
add a comma between bounced and onto.

Explanation:

The original sentence uses a comma correctly before the coordinating conjunction "and" to separate two independent clauses ("The cans struck the counter" and "then bounced onto the hard tiles of the kitchen floor"). The other proposed changes would introduce errors: adding commas between "cupboard and as" or "bounced and onto" is grammatically incorrect, and removing the comma before "and" would create a run-on between the two independent clauses.

Answer:

No change is necessary.