31. What is the name of the process by which water changes from a liquid to a solid?
A) Melting
B) Freezing
C) Boiling
D) Condensation
Answer: B) Freezing
32. Who discovered the principle of radioactivity?
A) Marie Curie
B) Antoine Lavoisier
C) Dmitri Mendeleev
D) Ernest Rutherford
Answer: A) Marie Curie
33. What is the name of the process by which energy is transferred from one object to another by contact?
A) Conduction
B) Convection
C) Radiation
D) Reflection
Answer: A) Conduction
34. What is the name of the process by which heat is transferred through a fluid by the movement of that fluid?
A) Conduction
B) Convection
C) Radiation
D) Reflection
Answer: B) Convection
35. Who discovered the first successful treatment for malaria?
A) Alexander Fleming
B) Paul Ehrlich
C) Robert Koch
D) Ronald Ross
Answer: D) Ronald Ross
