In 1740–1741 extremely cold temperatures struck vast areas of pre-industrial Europe, causing harvest failures that led to increased prices for staple food, famine, disease, excess mortality and migration. . . . Ireland was probably more vulnerable than most other European countries. Already in the first half of the eighteenth century, Irish food production was based heavily on potatoes and oats – a pattern of cultivation providing little resilience against the risk of harvest failure after an extremely cold winter. . . . Ireland was ill-prepared to deal with the consequences of harvest failure . . . Involvement in war (with Spain), religious conflicts, and the exclusion of the Catholic majority from political participation likewise affected food entitlements of large parts of the population. As a result, Ireland experienced excess mortality. –"The Irish Famine of 1740–1741,"
S. Engler, et al.

According to this passage, what were the causes of the 1740 famine in Ireland? Check all that apply.

extremely cold temperatures
a food supply dependent upon two crops
lower than normal mortality
war and religious conflict
protestants being excluded from political participation