Final answer:
A Software Developer typically needs programming skills in languages like Java and Python and expertise in optimizing database systems. This profession falls under the Tertiary economic sector, though the Quaternary sector could also apply.
Step-by-step explanation:
The career that typically requires programming expertise in languages such as Java and Python, in addition to skills in optimizing database systems, is D) Software Developer. Systems Administrators and Network Engineers usually focus on maintaining and managing the hardware and software that make up computer networks, without a deep focus on programming languages. Database Administrators do work with databases but are more focused on managing and organizing data than programming.
As for the sector of an economy a software developer would be in, the correct answer is c. Tertiary. The tertiary sector involves the provision of services rather than the production of goods. The quaternary sector, which includes jobs related to information technology and knowledge-based work, could also be argued as relevant to software developers with high specialization and focus on research and development.