Or: Is this the only factor that causes such tragedies? In that form, the singular factor matches with the verb causes. Your sentence mixes the plural rooms with the singular factor, making it hard for you to figure out which form the verb cause (s) should take.

Context Explanation

(This isn’t necessarily ungrammatical, but sometimes this can make a sentence ... In both situations there is a lack of resources which causes people to die. This sentence should be read as follows: there's a lack of some resources, and it is this lack that's causing deaths. In effect, without those resources people die; the resources help avoid death.

Insight Material

Unfortunately, there's a lack of those resources. This sentence makes sense, and is what you probably want to write. What causes coral bleaching ? What does cause coral bleaching ? What is the difference??

Final Conclusion

Which is grammatically correct? word choice - What causes X or What does cause X? - English Language ... The drug causes an adverse reaction in patients with a history of heart disease. So why "make" not "cause"? As Robusto says in the above comment, "make" just sounds less forceful and somewhat nicer.

However you could use either, depending on the context This drug makes me feel better (because I want to feel better) What causes you concern about the clauses’ having different subjects? Consider I thought she liked ice cream.