Match the following terms with the letters shown
Kidney
| 12. medulla
13. glucocorticoid secreting area
14. adrenal medulla
15. sex hormone secreting area

so here we go

atomic mass

239 + 1 = y + 134 + 3 combine like terms

240 = y + 137             subtract 137 from both terms

240 - 137 = y

103 = y

atomic number

94 = z +54 + 0

94 = z + 54               subtract 54 from both sides.

40 = z

answer

it's c (engineer's do their work with mechanical stuff not on any living being)