Select the two reasons that accounted for the stalemate in the war by 1916. naval blockades at sea british submarine warfare trench warfare policy of neutrality revolt in russia

The two reaseons are :

- Naval Blockades at sea

Which blockade all supplies from reaching their destinatin which make both side couldnt do a thing

- Trench Wardare

Which basically a type of land warfare using trenches that protected the troops from smile fire arms and artilery