Uber offers a$/$n $\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_$ that is essentially a published guideline on how other developers can embed Uber into their own apps.

a$.$

Cloud Endpoints

b$.$

SOAP $($Simple Object Access Protocol$)$

c$.$

EDA $($Event$-$Driven Architecture$)$

d$.$

API $($application programming interface$)$

e$.$

WebSockets protocol