Answer:
A complex sentence
Step-by-step explanation:
The stated sentence is a "complex sentence".
A complex sentence is a sentence that has one independent and at least one dependent clause. Whenever an independent clause and a dependent clause appear in a sentence, we can form a complex sentence.
In the above sentence, "Still, some credit must be given to early creative geniuses like Clark" is an independent clause.
"...who were able to stretch their imaginations..." is a dependent clause and "...and creativity to thrill audiences through the creation of the concept of special effects" is another dependent clause.
Therefore, the sentence is a "complex sentence".