Answer:
B). Morris ate a hamburger, which was full of grease and fat, at a diner.
Step-by-step explanation:
The second sentence employs the modifier correctly as it places the modifier('which was full of grease and fat') immediately followed by the noun it describes i.e. 'hamburger.' It is also punctuated correctly with the use of commas(,) at the beginning and end of the modifier. Thus, it appropriately justifies the rule. The other options are incorrect as they incorrectly place the modifier after the verb, besides other noun(which it doesn't describe), or in place of the subject. Thus, option B is the correct answer.