Question

dead leaves fell from the trees like snow, and the thermometer read fifty-five degrees. sinking into the warm sofa eli decided that raking the front yard could wait another day.

no change is necessary.
add a comma between sofa and eli.
add a comma between yard and could.
remove the comma between snow and and.

Explanation:

The phrase "Sinking into the warm sofa" is a participial phrase that modifies the subject "Eli". When an introductory participial phrase precedes the subject it modifies, a comma must separate the phrase from the main clause. The other options are incorrect: the comma before "and" correctly joins two independent clauses, no comma is needed between "yard" and "could", and the original comma after "snow" is proper.

Answer:

Add a comma between sofa and Eli.