An experimental design using litter-matching was employed to test a certain drug for cancer-causing potential. From each of 50 litters of rats, three females were selected; one of these three, chosen at random, received the test drug, and the other two were kept as controls. During a 2-year observation period, the time of occurrence of a tumor, and/or death from various causes, was recorded for each animal. One way to analyze the data is to note simply which rat (in each triplet) developed a tumor first. Some triplets were uninformative on this point because either (a) none of the three littermates developed a tumor, or (b) a rat developed a tumor after its littermate had died from some other cause. The results for the 50 triplets are shown in the table.30 Use a goodness-of-fit test to
evaluate the evidence that the drug causes cancer. Use a directional alternative and let α = 0.01. State your conclusion from part (a) in the context of this setting.

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Number of triplets 12 Tumor first in the treated rat Tumor first in one of the tw control rats No tumor Death from another cause Total 23 50