Question 1(Multipl no e Choice Worth 2 points)
(04.04 LC) b
Soybean type 1 yielded 125 bushels per acre last year at a research farm. This year, soybean type 2, planted in the same location, yielded only 100 bushels per acre and there was a
drought. The researchers do not know whether the difference is a result of the superiority of type 1 soybeans or the drought. What is this an example of?
O Bias
O Matched-pairs design
O The placebo effect
O Confounding variable
O Replication