The Gentlemen's Agreement a) "made Puerto Ricans citizens". b) restricted Japanese immigration. c) allowed Mexicans to cross over to America to take war jobs. d) promised that labor unions would not strike during the war. e) forbade German-Americans from registering for the draft.

B.) Restricted Japanese immigration

Explanation:

Gentleman's agreement was signed between Japan and US in 1907 - 1908. It was an effort by US president Theodore Roosevelt to calm down the tensions caused between the two countries due to immigration of the Japanese worker to US. A previous treaty with Japan had allowed free immigration but as the number of migrant workers grew in California the people became hostile towards the Japanese.

Japan had agreed in August 1900 to deny passports to the labourers who wanted to enter US but it didn't stop the inflow of Japanese workers. The workers obtained the passports on pretext of entering, Mexico, Hawaii, Canada and then entered the US.

To stop the Japanese a Korean and Japanese league was formed in USA in early twentieth century to exclude the Asians and under the pressure of the league, San Francisco school board made arrangements to shift all the Asia children to be placed in a segregated school.

Japanese government was furious due to these discriminatory steps taken against the Japanese people staying in US.

US signed the Gentleman's agreement because it was afraid of the Russian expansion in the Far East.

Under the agreement Japan agreed to deny passports to the labourers that wanted to enter US. It also accepted the US right to exclude those Japanese labourers who had the passports that were issued for other countries. The San Francisco School Board order was also withdrawn on behest of White house.