Using fluorescent microscopy, you observe the expected results, with protein secretion in normal cells, ER accumulation in mutant A, and Golgi apparatus accumulation in mutant B. You also express the GFP-fusion protein in double-mutant yeast cells containing mutations in both the gene underlying mutant A and the gene underlying mutant B. What is the correct location and explanation for where the GFP-fusion protein will accumulate in these A and B double-mutant yeast cells