You are concerned with surveying the protozoa in the arboretum soil. While most commonly thought to live exclusively in aquatic environments, protozoa can play an important role in the nutrient cycling that takes place in soil. In addition, protozoa can help maintain the proper balance of bacterial populations within soil, as bacteria are a primary source of food for protozoa.
Protozoa are extremely diverse. However, there are three characteristics common to all organisms called protozoa. What are these three characteristics?

Choose the answer that best describes the three characteristics common to all protozoa.

eukaryotic, contain chloroplasts, produce energy via mitochondria
eukaryotic, use cilia for motility, produce energy via mitochondria
eukaryotic, unicellular, lack a cell wall
eukaryotic, reproduce sexually, contain chloroplasts

eukaryotic, unicellular, lack a cell wall

Explanation:

The protozoa are eukaryotic, unicellular animals whose cell lack cell wall. In addition, they posses the following characteristics:

They live as either free living or parasite in nature. As such, they feed heterotrophically.They are mostly motile through the use of organs like cilia. pseudopodia or flagella.Their size ranges from one micron to several millimeters.They mostly reproduce by binary fission.

Mantle convection  is the slow  creepingmotion of earth's solid silicate  mantle  caused by  convection  currents carrying  heat from the interior  to the planet's surface.[1][2]  the earth's surface  lithosphere, which rides atop the  asthenosphere  (the two components of the  upper mantle), is divided into a number of  plates  that are continuously being created and consumed at their opposite  plate boundaries. accretion occurs as mantle is added to the growing edges of a plate, associated with  seafloor spreading. this hot added material cools down by  conduction  and  convection  of heat. at the consumption edges of the plate, the material has thermally contracted to become dense, and it sinks under its own weight in the process of  subduction  usually at an  ocean trench.[3]this subducted material sinks through the earth's interior. some subducted material appears to reach the lower mantle,[4]  while in other regions, this material is impeded from sinking further, possibly due to a phase transition from  spinel  to  silicate perovskiteand  magnesiowustite, an  endothermic reaction.[5]the subducted oceanic crust triggers  volcanism, although the basic mechanisms are varied. volcanism may occur due to processes that add buoyancy to partially melted mantle causing an upward flow due to a decrease in density of the partial melt.secondary forms of convection that may result in surface volcanism are postulated to occur as a consequence of intraplate extension[6]  and  mantle plumes.[7]it is because the mantle can convect that the  tectonic plates  are able to move around the earth's surface.[8]mantle convection seems to have been much more active during the  hadean  period, resulting in gravitational sorting of heavier molten  iron, and  nickel  elements and  sulphides  in the core, and lighter  silicate minerals  in the  mantle.

Im assuming this is a multiple choice answer what is the answers to chooce from?