when/though

[diamondcutter]

I read this test question in a grammar forum.

How silly it is to travel out by high-speed rail _____you can take a plane, which is much cheaper.

A.while B.when C.since D.though

(Source: https://www.cpsenglish.com/question/39565)

The answer key is B. I think D is also OK. What do you say?

 

[tedmc]

No, "though" which is associated with the opposite does not fit the blank.

 

[GoesStation]

The correct answer is "when". The question should say to travel by high-speed rail. The word "out" doesn't belong there.

 

[probus]

I agree that when is the best answer, but I think C (since) is also possible.

 

[emsr2d2]

I read this test question in a grammar forum.

How silly it is to travel [STRIKE]out[/STRIKE] by high-speed rail _____ space here you can take a plane, which is much cheaper.

A. while
B. when
C. since
D. though

(Source: https://www.cpsenglish.com/question/39565)

The answer key is B. I think D is also OK. What do you say?

Only B works for me, with the opening "How silly it is to ...". I could fit A and C into slightly different sentences. If D had said "even though", I could fit that into another variation.