What is the most appropriate service model to recommend?

You have been approached by a company to recommend a service model given the following economic drivers:

– 65% of developer effort is spent on maintenance

– There is a lack of reusable development components

– Multiple development environments are being instantiated without standardization

– There is a need for software minimum customization

In addition, developers would like independent control to test and provision their own environments.

What is the most appropriate service model to recommend?
A . PaaS
B . BaaS
C . IaaS
D . SaaS