Explanation:

To identify the scientific computer language, we must consider the primary design purpose of each option. **Fortran (c)**, an acronym for FORmula TRANslation, was specifically designed in the mid-1950s for scientific and engineering applications. Its robust capabilities for numerical computation, array processing, and mathematical functions made it the dominant language for high-performance computing in scientific research. **Basic (a)** (Beginner's All-purpose Symbolic Instruction Code) was designed as a general-purpose language for beginners, not specifically for scientific computing. **Cobol (b)** (COmmon Business-Oriented Language) was explicitly developed for business, finance, and administrative data processing. **Pascal (d)** is a general-purpose, structured programming language primarily used for teaching programming concepts. While Basic and Pascal can perform scientific calculations, FORTRAN was engineered from the ground up to excel in scientific and engineering domains, making it the definitive scientific computer language among these choices.