Q16

[vik]

The author appears to discuss naturally occurring PF in para 1 to explain the wheat fields experiment. Hence I chose ans D. Where did I go wrong?

[peg_city]

The answer is D

[alovitt]

I chose D, but kept B as a contender. Is B wrong because the author doesn't "explain" why the yields increased, but merely states it and assumes the antagonist caused the increase. So would it be better to say that yield increases function as an example of the benefits Pseudomonas fluorescens bring about rather than Pesudo whatever "explaining" the yield increases? I also found D a bit vague, especially the background info bit. My prephrase was actually "it provides example of benefits that using this antagonist has on crop yields."

[timmydoeslsat]

The point of the author discussing PF in the first paragraph was to show how a bacteria could be beneficial for crops against phytopathogens.

The wheat yields experiment was simply supporting that idea! If anything, B is the reverse. The purpose of B was to support the contention made of PF.

And of course the reason behind talking about PF in the first place is to set us up for the idea of this research being fruitful.

[maryadkins]

The key on this type of question is to hone in on "primarily." What's the PRIMARY purpose of discussing the PF? Not to explain why the yields increased.

Also, another nitpicky reason (B) is wrong is that the PF discussed in the first paragraph is not "altered." Genetic alteration isn't brought up until the second paragraph.