Which one would you pick out of these two options if you really had to pick only one?

1) To find a cure for all types of mental illnesses

2) to find a cure for all types of cancer.

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3 d
Cancer is terrible but if I had to pick I would still prefer more to fully cure all mental illnesses like depression, PTSD, anxiety, bipolar, sczhiophrenia, psychopathy, sociopathy and ADHD etc
Which one would you pick out of these two options if you really had to pick only one?
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