I believe, though am sure I'll be corrected if I'm wrong, that if the sound of the word ending in s doesn't change when pluralised, it's just the ', if the sound changes, you should have 's. Since it would sound like "Jesuses" rather than "Jesus" it should be "Jesus's".
Is the correct answer as it is possessive and they are the disciples belonging to Jesus....assuming you can use the word possessive when speaking of Jesus not in an exorcist sort of way
Eg, if a family has a house, it's the family's home. If your talking about multiple families, it would be the families' homes (sound it out, it sounds the same as the first 'families').
[Jesus's] Is the correct answer as it is possessive and they are the disciples belonging to Jesus....assuming you can use the word possessive when speaking of Jesus not in an exorcist sort of way