Quiz for React

Q1: What is React primarily used for?

A. A. Building user interfaces B. B. Database management C. C. Server-side scripting D. D. Operating system development

Q2: Who developed React?

A. A. Google B. B. Facebook C. C. Microsoft D. D. Twitter

Q3: React follows which programming paradigm?

A. A. Object-oriented programming B. B. Functional programming C. C. Procedural programming D. D. Logic programming

Q4: Which of these is a core concept in React?

A. A. Virtual DOM B. B. Direct DOM manipulation C. C. Server-side rendering only D. D. None of the above

Q5: What language syntax does React primarily use?

A. A. HTML B. B. JSX C. C. XML D. D. Python

Q6: Which command creates a new React app using Create React App?

A. A. npx create-react-app my-app B. B. npm install react C. C. react new app D. D. npm start react-app

Q7: What is a React component?

A. A. A reusable UI piece B. B. A database C. C. A server D. D. A CSS style

Q8: React components can be written as:

A. A. Functions only B. B. Classes only C. C. Functions or classes D. D. HTML only

Q9: How does React update the UI?

A. A. Direct DOM manipulation B. B. Virtual DOM diffing C. C. Refreshing the whole page D. D. Server refresh

Q10: Which hook is commonly used for managing state in functional components?

A. A. useState B. B. useEffect C. C. useContext D. D. useReducer

Q11: What is JSX?

A. A. A CSS framework B. B. A templating language C. C. A syntax extension combining JavaScript and XML D. D. A database query language

Q12: How are events handled in React?

A. A. Using camelCase syntax B. B. Using lowercase syntax C. C. Using HTML attributes D. D. Using CSS selectors

Q13: Which tool helps to manage side effects in React?

A. A. useState B. B. useEffect C. C. useContext D. D. useReducer

Q14: What is the purpose of keys in lists?

A. A. To uniquely identify elements B. B. To style elements C. C. To add classes D. D. To sort elements

Q15: Which of the following is NOT a feature of React?

A. A. Virtual DOM B. B. Two-way data binding C. C. Component-based architecture D. D. Declarative UI

Q16: What does "props" stand for in React?

A. A. Properties passed to components B. B. Private variables C. C. Global variables D. D. Internal state

Q17: How do you pass data from parent to child components?

A. A. Using props B. B. Using state C. C. Using context only D. D. Using Redux only

Q18: What is the default port for React development server?

A. A. 3000 B. B. 8080 C. C. 5000 D. D. 80

Q19: How do you include CSS styles in React?

A. A. Import CSS files in components B. B. Inline styles only C. C. External CSS only D. D. Styles cannot be applied