According to Apigee and Google's API design best practices, consistency is a foundational principle for creating a usable and predictable API. While the initial choice of a name is important for intuitiveness, the most critical practice is to apply that name consistently across the entire API surface. An inconsistent API (e.g., using customerId, customerid, and custID for the same concept in different places) increases the cognitive load on developers and leads to errors. Therefore, establishing a naming convention and adhering to it rigorously is paramount.

A. Allow each developer to make their own choice.

This approach leads directly to inconsistency, making the API difficult to learn, use, and maintain. It is a recognized anti-pattern in API design.

B. Use the same field name as in the back end system.

This practice tightly couples the API to the backend implementation, exposing internal details that may be cryptic or irrelevant to the consumer and hindering future backend refactoring.

C. Survey typical consumers to determine which common name to use.

While designing for the consumer is a key principle and surveying is a good method to achieve intuitiveness, consistency is a more fundamental and non-negotiable rule. An API must be consistent, even if user surveys are not conducted.

1. Google Cloud API Design Guide

Naming Conventions: This guide

which informs Apigee's philosophy

states

"To provide a consistent developer experience across a large number of APIs and over a long period of time

all names used by an API should be: simple

intuitive

consistent." It further emphasizes

"Within a given API

names must be used consistently." This highlights consistency as a mandatory rule.

Source: Google Cloud. (n.d.). API Design Guide: Naming Conventions. Retrieved from https://cloud.google.com/apis/design/namingconvention

2. Apigee

Web API Design: The Missing Link (e-book): This official Apigee publication lists "Strive for Consistency" as a core design principle. It explains

"Consistency in your API design will make it easier for developers to learn and use. ... Be consistent in your use of name casing (camelCase or underscores)." This directly supports the mandate for consistency presented in the correct answer.

Source: Marsh

D. (2016). Web API Design: The Missing Link. Apigee. (Specifically

the chapter on "Design Principles").

3. Stanford University

CS193P - Developing Apps for iOS: Course materials on API design frequently emphasize the "Principle of Least Astonishment

" where consistency is a key component. An API should not have surprising or unpredictable behavior

which includes consistent naming for similar concepts.

Source: Stanford University. (2021). CS193p - Developing Apps for iOS. Lecture materials on API Design. (General principle taught in software engineering and API design modules).