Why was Archduke Francis Ferdinand assassinated? How did Austria-Hungary react?

Ignore warning Ng of the anti-Austrian sentiment in Serbia an traveled to Serbia.

The Austrian reacted by using death of the Archduke as a pretext to crush Serbia, ignoring what Russian may be...

(a) He ignored warnings of anti-Austrian sentiments in Serbia and traveled there on its independence day from Turkish rule. A terrorist group called the Black Hand wanted to kill him and show that they could not be repressed by foreign oppressors.

(b) Although the Austrian emperor, Francis Joseph, wanted to avoid war his government in Vienna thought otherwise and used it as an excuse to crush Serbia. Austria told Serbia that it had to first, end all anti-Austrian feelings and punish any Serbian official involved in the murder plot, allowing Austria to join in on it as well.