What is the correct sequence of the following step in the fabrication of a monolithic, bipolar junction transistor?
1. Emitter diffusion
2. Base diffusion
3. Buried layer formation
4. Epi-layer formation
Select the correct answer using the codes given below

A

3, 4, 1, 2

B

4, 3, 1, 2

C

3, 4, 2, 1

D

4, 3, 2, 1