The correct options are
A Attacks on goods caravans by bandits.
B Theft of their wares.
D High taxes on their goods.
If a single trader expressed displeasure with high taxes, rulers were unlikely to acknowledge the impact of high taxes. So, traders of the past decided to form a group to negotiate with rulers. Such groups were called ‘Guilds’. If a bunch of traders presented their problems to rulers, they were more likely to succeed in achieving their goal. The ruler would be convinced about the existence of a problem. He would also be wary of angering many tax paying traders. Traders could inform the king about the need for protection for their goods, and the taxes imposed on them. They, however could not inform the kings about problems faced in foreign lands.