Final answer:
First Lady Michelle Obama's argument in her speech promoting Drink Up is a cause and effect-argument.
Step-by-step explanation:
The type of argument used by First Lady Michelle Obama in this excerpt from her speech promoting Drink Up is D. A cause and effect-argument. She states that as a result of the nationwide marketing campaign for water launched by Drink Up, bottled water sales went up three percent among those who saw the ads. This shows a direct causal relationship between the campaign and the increase in sales.