Of grammar rules but the basic ones refer to sentence structure and parts of speech, which are noun, pronoun, verb, adjective, adverb, preposition and conjunction. Let’s look at the way sentences are put together and the words that form them.

Basic English Grammar Rules
Some of the most basic and important English grammar rules relate directly to sentence structure. Some of these rules specify that:
A singular subject needs a singular predicate.A sentence needs to express a complete thought.
Another term for a sentence is an independent clause.
Clauses, like any sentence, have a subject and predicate too. If a group of words does not have a subject and predicate, it is a phrase.If they can stand alone and make a complete thought, then they are independent and called sentences.If they do not express a complete thought, they are called "dependent clauses." An example of a dependent clause, which is not a sentence, is “when i finish my work”.
The correct answer is 4: Cassius cannot believe that a weakling like Caesar has become so great. Cassius complains of being forced to bow before Caesar (he "must bend his body If Caesar carelessly but nod on him"), and the fact that Caesar has suffered from fevers and seizures makes his submission to him all the more enraging. Cassius does not believe himself to be less than any other man, much less one who has such weak health.
I believe the answer is: A. Dante believed that a sinners punishment should be a serve as his sin
In Dante's inferno, hell is divided into several levels, and the punishment/torture that given to humans would be most severe as the sinners go down to the lower levels. The first level on Dante's circle of hell is given to the people who do not believe in Christianity while the lowest level is given to the traitors of christianity.