Meaning: 'Survivors' refers to people who have lived through an event, in this case, individuals who have recovered from smallpox and are now immune.

Wrong options:

• people: While 'people' is a general term for individuals, it lacks the specific context of having overcome the disease, making it less precise here.
• victims: 'Victims' implies those who suffered from the disease, but does not indicate survival or immunity, which is crucial to the context.
• patients: 'Patients' refers to individuals receiving medical treatment, but does not convey the idea of having survived the disease, thus not fitting the context.

Correct answer: provided

Explanation: The word 'provided' is the correct choice as it indicates the action of supplying immunity, fitting grammatically in the past tense and contextually in describing the outcome of variolation.

Meaning: 'Provided' means to supply or make available, in this case, immunity from further infection after variolation.

Wrong options:

• contributed: 'Contributed' suggests a partial role in giving immunity, which does not fit the direct causative context of the sentence.
• gave: 'Gave' is grammatically correct but less formal and precise than 'provided,' which is more suitable for the scientific context.
• transferred: 'Transferred' implies a movement from one place to another, which does not accurately describe the process of immunity being established.

Correct answer: common

Explanation: The term 'common' accurately describes the widespread acceptance and practice of variolation during the 1700s, fitting grammatically as an adjective that modifies 'practice.'

Meaning: 'Common' means widely practiced or prevalent, indicating that variolation was a regular method used in those regions.

Wrong options:

• same: 'Same' does not fit contextually as it does not convey the idea of frequency or prevalence in practice.
• usual: 'Usual' implies normalcy but lacks the emphasis on widespread acceptance that 'common' provides.
• frequent: 'Frequent' suggests occurrence but does not capture the idea of being a standard practice as effectively as 'common' does.

Correct answer: fatalities

Explanation: The word 'fatalities' is the most appropriate choice as it specifically refers to deaths caused by smallpox, fitting grammatically as a plural noun that aligns with the context of discussing the impact of variolation.

Meaning: 'Fatalities' refers to deaths resulting from a particular cause, in this case, deaths from smallpox.

Wrong options:

• patients: 'Patients' refers to individuals receiving treatment and does not convey the idea of death, making it unsuitable in this context.
• diseases: 'Diseases' is a general term for illnesses and does not relate to the number of deaths, thus not fitting the context of mortality.
• victims: 'Victims' implies those affected by the disease but does not specifically denote deaths, making it less precise than 'fatalities'.