An independent clause is a clause that can stand alone as a sentence. Every sentence must contain a subject and predicate and express a complete thought.
Dependent clauses are clauses that can't stand alone as they don't contain all elements of a sentence. Their purpose is to provide additional information about what is stated in the independent clause.
A simple sentence is a sentence that consists of one independent clause.
A compound sentence is a sentence that consists of at least two independent clauses.
A complex sentence is a sentence that consists of one independent clause and at least one dependent clause.
The given sentence consists of one independent (..<em>. control your sugar intake to stay healthy</em>) and one dependent clause (<em>Because sugary snacks and drinks are unhealthy...</em>), which makes it a complex sentence.
I can't really answer question 3 or 5 due to not seeing the passage or the picture to said passage, but I can answer question 4 for you. I would say the answer to 4 would be a.
