Final answer:
In Drosophila, the XXY chromosome complement would typically determine a female phenotype, making the triploid fly a female. However, triploidy can lead to developmental issues and sterility.
Step-by-step explanation:
In Drosophila, or fruit flies, sex determination is based on the ratio of X chromosomes to sets of autosomes rather than the presence of a Y chromosome. Normally, Drosophila males are XY and females are XX, but in this case, the fly is triploid with a sex chromosome complement of XXY. Considering the rules of Drosophila sex determination, the presence of two X chromosomes typically indicates a female phenotype. However, the triploidy makes this situation unusual, and the actual phenotypic outcome might vary.
Without specific reference to triploidy outcomes in Drosophila and given the standard understanding of sex determination in Drosophila, the most accurate answer would be that this fly is a female (b). Nonetheless, it is important to note that triploidy in fruit flies can potentially lead to developmental issues and sterility. The provided option (c) sterile would also be a consideration, however, given the choices and based on typical sex determination, 'female' is the best answer. Answer (a) male is incorrect as males are XY, not XXY, and answer (d) intersex does not apply as sex determination in Drosophila does not typically result in intersex phenotypes with such chromosome complements.