How many genes are affecting the phenotype in a complementation analysis?

I'm studying for an exam and trying to figure out this question but I keep getting confused.  So this is in drosphila, legs are either elongated( wild-type) or crumpled/ gnarled (mutant).  Its asking how many genes affect the leg phenotype.  So i thought for this one you would look at where it is a - on the table( for malformed legs). so its saying the answer is that there are 3(#1 and #4, #2, #3, and #5.  The 1 and 4 are on the first row.  But I'm showing those are the places where are are minus signs but the key is saying that there are only 3 genes.  I'm confused. Can someone explain to me how to find how may genes are affected?