Lonic bonds
form compounds with low melting and boiling points
are very strong in water
occur when atoms share electrons
are held together by strong electrical forces

Ionic bonds are bond formed when cation and ion combined together is by transferring of electron so as to acquire Noble gas configuration

From question choice is

are held together by strong electrical forces and are able to dissolve in water

answer: national resource conservation services

national resource conservation services is the us. based approach that provides technical and financial assistance for natural resource management. nrcs society in conservation of resources by involving in activities like farmland protection, flood prevention, watershed protection, urban conservation, conserves economic and environmental conditions. it conducts soil surveys and implements the policy of natural resources management on the society.

answer : haversian

[explanation: -(compact bone is organized as parallel columns, known as haversian systems, which run lengthwise down the axis of long bones. these columns are composed of lamellae, concentric rings of bone, surrounding a central channel, or haversian canal, that contains the nerves, blood vessels, and lymphatic system of the bone)]