The test for goodness of fit a. is always an upper tail test. b. is always a two-tailed test. c. can be a lower or an upper tail test. d. is always a lower tail test.

a. is always an upper tail test.

Step-by-step explanation:

The chi-square goodness-of-fit test is a test to check whether the sample comes from the population with the expected distribution or not.

If the observed frequency is close to the expected frequency, then the square of the deviations will be small. The square of the deviation is divided by the expected frequency to get the weighted frequencies.

If the sum of these weighted squared deviations is large is then it creates a doubt for the distribution claimed other wise not. Therefore, the chi-square goodness-of-fit test is always a right tail test.

Hence correct option is "a. is always an upper tail test. "

all it means is function 3