Choice "D" is correct. Development or improvement of techniques and processes is a research and development (R&D) cost.
Choice "a" is incorrect. Offshore oil "exploration" costs (assumed to be geological and geophysical expenses) that is the primary activity of a company is not an R&D cost. These costs would be expensed (as cost of services sold) by a company whose primary activity is the incurring of such geological and geophysical costs. If these "exploration" costs are not assumed to be geological and geophysical expenses, they would be the drilling of exploratory wells looking for commercial oil & gas deposits; in that event, they would be capitalized and then amortized. Either way, the costs are not an R&D cost.
Choice "b" is incorrect. Research and development performed under contract for others is not an R&D cost. The purchaser buying the research and development will be able to expense its expenditures as R&D costs.
Choice "c" is incorrect. Market research, even though the term contains the word research, is not an R&D cost.