What or the?

[hoangkha]

Hi!
- High and low atmospheric pressure systems are ________ cause changing weather patterns.
A-the
B-whose
C-which
D-what
The key is D, but I am wondering whether it is possible to be A, please.

 

[Peter Chan]

"what" refers to "High and low atmospheric system"

"cause" is a verb, not a noun.

The sentence means "Changing weather patterns are caused by high and low atmospheric pressure system".

"the" is to used if the sentence is written as " High and low atmospheric pressure systems are ___the_____ causes of changing weather patterns"

Here "causes" is a nouns, it refers to the " High and low atmospheric pressure system".

 

[MikeNewYork]

Hi!
- High and low atmospheric pressure systems are ________ cause changing weather patterns.
A-the
B-whose
C-which
D-what
The key is D, but I am wondering whether it is possible to be A, please.

A could only work if the ending changed to "causes of".

 

[SoothingDave]

"Cause" is a verb and a noun.