Too many present perfect tenses

[kiranck007]

Hi, I find this topic loaded with present perfect tenses, but I don't see any cue on the past event. Can someone explain this please.

Fusion, the process through which the sun produces heat and light, has been studied by scientists, some of whom have attempted to mimic the process in their laboratories by blasting a container of liquid solvent with strong ultrasonic vibrations.


Fusion, the process through which the sun produces heat and light, has been studied by scientists,
Fusion, the heat and light produced by the sun, has been studied by scientists,
Fusion, the process through which heat and light are produced by the sun, has been studied by scientists,
Scientists have studied fusion, the process the sun uses to produce heat and light,
Scientists have studied fusion, the process the sun uses to produce heat and light, and

[RonPurewal]

Hi,
This folder is for GMAT PREP SOFTWARE problems ONLY. This doesn't look like a problem from that software.

Accordingly:

* If this problem actually *is* from the GMAT PREP software, please post a screenshot of the problem, directly from the software.

* If it's not, then re-post your question in the General Verbal thread, along with an explicit citation of the original source (= original authorship -- not another forum or other secondhand source).

Unless this is proven to be a GMAT PREP problem, we'll delete this thread in a few days. thanks.

[kiranck007]

Hi, Ron.
This is from CAT exams.I don't see any option to upload the screenshot here. Here is the URL to the problem. https://www.manhattangmat.com/onlineexa ... tionid=624

[RonPurewal]

Ok. Well, this is the wrong folder, then. Please re-post your query in the CAT Verbal section.

Thanks.