Read the sentence. neither schools nor banks are open on the third monday in january because it is a national holiday honoring dr. martin luther king, jr. what is the subordinating conjunction in the sentence?

The subordinating conjunction in the sentence is "because".

Explanation:

Subordinating conjunctions are those parts of speech that joins two clauses together, with one clause being a dependent clause and the the other an independent clause. In the provided sentence,

 "Neither schools nor banks are open on the third Monday in January because it is a national holiday honoring Dr. Martin Luther King, Jr",

the "Neither schools nor banks are open on the third Monday in January" is the independent clause and "it is a national holiday honoring Dr. Martin Luther King, Jr" is a dependent clause. And joining these two clauses is "because". Thus, it is the subordinating conjunction as it joins the two clauses- dependent and independent clauses.