Answer:
To strengthen the argument, sentence number 4 must present evidence to prove and justify what the author is presenting.
Explanation:
Although the text presented in the question above is coherent and cohesive, it presents a weakened argument, which could be improved with the addition of supporting details and evidence.
This argument is presented in sentence number 4, where the author states that the government needs to act, to provide health services free of charge to all citizens. In this case, to strengthen this argument, the author of the text could present ways that the government could act to provide these services, in addition to showing how governments in other countries acted and the improvements that were achieved with this. Another alternative would be to show how the lack of a free health service is harmful to the population, through real examples that confirm this.
Evidence and supporting details are statements that confirm an author's arguments, showing how the arguments presented are true and correct.
